Utahns began petitioning Congress for admission to the Union in 1849 but did not achieve statehood until 1896. During most of Utah's territorial years federally appointed men, all non-Mormons except for Brigham Young, served as territorial governors. They repeatedly clashed with the Mormon-dominated legislature. While the number of non-Mormons living in Utah was less than 10 percent, they lived mostly in the cities or in mining and railroad towns. There were several reasons the non-Mormon minority felt fearful of Mormon control: polygamy, church and state issues, and lack of free public schools.

Polygamy still held the country's attention. Congress passed the Anti-bigamy Act (1862), but it was generally not enforced. Finally, in 1887 the Edmunds-Tucker Act brought an end to the LDS church corporation and threatened the survival of all Mormon institutions. Additionally, women, who had the vote under territorial law, did not have the right to vote by this act. Clearly something dramatic had to be done. In September 1890 Mormon church president Wilford Woodruff issued the Manifesto. It stated that Mormons no longer accepted polygamy.

In 1891, the Democratic and Republican political parties were organized in Utah. With each of these steps, Utah moved closer to becoming a state. Careful teamwork by Mormons and non-Mormons in Washington, D.C., and positive statements by the Utah Commission led to the passage of the Enabling Act. Signed by President Grover Cleveland, this bill allowed Utahns to hold a constitutional convention and apply for admission to the Union. That convention was held in 1895. On January 4, 1896, Utah became the 45th state. Utah women campaigned successfully for the return of their right to vote. They received a full equal rights provision in the new state constitution.

Beginning in 1865, Utah's Black Hawk War developed into the deadliest conflict in the territory's history. Chief Antonga Black Hawk died in 1870, but fights continued to break out until additional federal troops were sent in to suppress the Ghost Dance of 1872. The war is unique among Indian Wars because it was a three-way conflict, with mounted Timpanogos Utes led by Antonga Black Hawk exploited by federal and LDS authorities.

On May 10, 1869, the First Transcontinental Railroad was completed at Promontory Summit, north of the Great Salt Lake. The railroad brought increasing numbers of people into the state, and several influential businesspeople made fortunes in the territory.

During the 1870s and 1880s, laws were passed to punish polygamists, and in the 1890 Manifesto, the LDS Church banned polygamy. When Utah applied for statehood again, it was accepted. One of the conditions for granting Utah statehood was that a ban on polygamy be written into the state constitution. This was a condition required of other western states that were admitted into the Union later. Statehood was officially granted on January 4, 1896.